The present invention relates generally to particle conveying devices and more particularly to pneumatically assisted hopper filling devices for use in the pharmaceutically industry.
Pneumatic assisted conveying devices are well known in the art and provide an efficient and economical solution to the transportation of such materials. For example, U.S. Pat. No. 351,854 to Delhaye discloses a device for elevating and transporting granular matters to any height or distance by means of compressed air jets. Likewise, U.S. Pat. No. 628,187 to Sibley discloses a suction or injector conveyor elevating or conveying liquids or solids by pneumatic means.
A more recent example of a pneumatic conveyor is shown in U.S. Pat. No. 4,774,636 to Whitlock which discloses a hopper loader of the type that transports and elevates coarse or finely ground granularized or pelletized material. An apparatus for conveying electrostatically applied paint powder is disclose in U.S. Pat. No. 4,105,256 to Parker et al. In U.S. Pat. No. 3,876,352 to DeTroyer et al., a collecting mechanism for parts made by a powder compacting apparatus is disclosed where a portion of the mechanism consists of an aspirator that creates a partial vacuum to pick up small parts and transfer them to a discharge station. And, U.S. Pat. No. 4,358,226 to Nagata et al. discloses a method for conveying articles by air flow.
While devices such as these can provide a strong and reliable manner of moving particle matter, they are frequently too rough for certain more delicate materials such as gelatin capsules. This problem was addressed in U.S. Pat. No. 4,411,388 to Muck which shows an apparatus for conveying lightweight particulate matter which provides for minimal disruption of the structural integrity of the particles as they are being transported.
What is needed in an apparatus for conveying particle matter which minimizes damage to the conveyed material during operation.